Automatic sewage treatment and disposal unit



Jan. 15, 1957 G. P. scHUMAcKER ETAL 2,777,816 AUTOMATIC SEWAGE TREATMENT AND DISPOSAL. UNIT Filed Sept. 7, 1951 5 Sheets-Sheet 2 Byemv d M//a/AMS G. P. SCHUMACKER TAL AUTOMATIC SEWAGE TREATMENT AND DISPOSAL UNIT 5 Sheets-Sheet 5 IN1/EN ToR Wise-@raw Ma/AMS @Kam/f 7%@ Med WWW l ra 5X5 Jan. 15, 1957 G. P. scHUMAcKER HAL 2,777,816

AUTOMATIC SEWAGE TREATMENT AND DISPOSAL UNIT 951 5 Sheets-Sheet 4 Eo QE Filed Sept. 7, l

Jan 15, 1957 G. P. scHUMAcKER ErAL 2,777,816

AUTOMATIC sEwAGE TREATMENT AND DISPOSAL UNIT Filed sept. 7, 1951 5 Sheets-Sheet 5 AIT/- United States Patent AUTOMATIC SEWAGE TREATMENT AND DISPOSAL UNIT George P. Schumacker, Lakewood, and Egerton B. Williams, Bay Village, Ohio, assignors to The American Ship Building Company, Cleveland, Ohio, a corporation of New `lersey Application September 7, 1951, Serial No. 245,572 12 Claims. (Cl. 2102) This invention relates to sewage treatment and disposal apparatus and, as one of its objects, aims to provide improved apparatus of this kind in which the component parts are all assembled in connected relation to constitute a factory-built unit adapted to be tested and transported as such prior to installation in its final location. The improved sewage treatment and disposal apparatus of this invention is especially suitable for ships and accordingly is hereinafter described as applied to that use but without any intention of limiting `the apparatus in that respect since it can also be used to serve schools, factories, municipalities and the like.

Another object of this invention is to provide improved sewage treatment and disposal apparatus embodying tank structure having sewage receiving and treating chambers and including transfer and delivery pumps which operate, respectively, to transfer sewage from the receiving chamber to the treating chamber and to deliver the efl'luent from the treating chamber to a disposal point, and in which such pumps are automatically controlled in response to predetermined changes in the level of liquid in the chambers such that these pumps operate in sequence with the transfer pump preferably oper-ating only while the delivery pump is stopped and the delivery pump preferably operating only while the transfer pump is stopped.

Still another object of the invention is to provide improved sewage treatment and disposal apparatus of the character just mentioned which ical supply means including a pump having delivery means by which the chemical can be mixed with sewage supplied to the treating chamber and, if desired, can also be mixed with the sewage of the receiving chamber.

A further object is to provide improved sewage treating and disposal apparatus of this character in which the receiving chamber comprises a solids collecting compartment and a liquid collecting compartment, and in which the automatic control of the delivery pump is responsive to a predetermined change in the liquid level of the liquid collecting compartment.

Yet another object is to provide impro-ved sewage treatment and disposal apparatus of the character mentioned in which valve and conduit means connecting the transfer and delivery pumps with the tank structure permits the delivery pump to be used as a transfer pump when desired or the transfer pump to be used as a delivery pump, and in which either of these two pumps can be used as a sludge discharge means for emptying the solids collecting compartment of the receiving chamber.

As another of its objects this invention provides improved sewage treatment and disposal apparatus of the character referred to in which the valve and conduit means includes a conduit loop having one end thereof connected with the treating chamber and its other end adapted for connection with the point of effluent disposal, and in which the transfer and delivery pumps have their discharges connected with an intermediate portion of such conduit loop.

embodies a treating chemi It is also an object of this invention to provide improved sewage treating and disposal apparatus of the kind above referred to in which a tank containing the sewage receiving and treating chambers, together with `the transfer and delivery pumps, are mounted on a common base and are connected in operative relation by the valve and conduit means to constitute a prefabricated factory-built unit adapted to be tested as such and then shipped as an assembled unit to an installation point.

The invention can be further brieiiy summarized as consisting in certain novel combinations and arrangements of parts hereinafter described and particularly set out in the claims hereof.

In the accompanying sheets of drawings,

Fig. 1 is a side elevation showing a sewage treatment and disposal apparatus embodying the present invention and having the form of a substantially complete prefabricated factory-built unit;

Fig. 2 is a longitudinal transverse section taken through the apparatus substantially as indicated by the irregular section line 2 2 of Fig. l;

Fig. 3 is a top plan view of the apparatus;

Fig. 4 is an end view of the apparatus;

Fig. 5 is a fragmentary vertical section showing a sounding device for determining the depth of .accumulated solids in the solids collecting compartment;

Fig. 6 is a mechanical diagram, mainly in longitudinal section, showing the pumping system embodied in the apparatus;

Fig. 7 is a chart showing the open and closed condition of -the main valves for accomplishing different pumping operations in the functioning of the apparatus; and

Fig. 8 is a wiring diagram illustrating electrical control means embodied in the apparatus.

As one practical embodiment of the sewage treating and disposal apparatus of this invention, the drawings show a tank 10 mounted on a base 11 and containing sewage receiving and treating chambers 12 and 13. This improved apparatus also comprises, in general, a pair `of transfer and delivery pumps 14 and 15 which are driven by motors 16 and 17 and whose functions will be described hereinafter, and a treating -chemical supply pump 18. Additionally, this apparatus includes conduit means and valves by which these components are connected in operative relation, as will be explained hereinafter. The driving motors 16 and 17 are here shown as being electric motors although steam turbines could be used if desired.

As one important feature of the present invention, the improved sewage treatment and disposal apparatus embodying the components just mentioned, is in the form of a compact, prefabricated unit 19, which is completely assembled and tested in a shop or factory and can then be transported as such a complete and tested unit to a point of final installations or to a point where it will be embodied in a ship structure. The invention contemplates that the prefabricated and tested unit 19 can be disassembled or partially disassembled, to facilitate handling or shipment thereof or movement thorugh hatches, doorways or the like.

The base 11 can be any suitably constructed supporting base which, `in this instance, is in the form of a substantially horizontal rigid frame composed of suitably connected longitudinal and transverse frame members 20, 20a and 2 1. The base 11 also includes foundations 22 and 23 on which pump assemblies embodying the transfer and delivery pumps 14 and 15 are mounted. The foundations 22 and 23 constitute reinforced portions of the base 11 and are located at longitudinally spaced points along the front of the later. The transfer pump 14 and its driving motor 16 are suitably mounted on a base 24 to constitute a transfer pump assembly which is, in turn,

affermare suitably secured to the foundation 22. The delivery pump and its driving motor 17 are suitably mounted on a base 2S to constitute a discharge pump assembly which is suitably secured to the" foundation 23.

The tank 10 is here shown as being an elongated tank structure which is located in spaced relation above the base 11 and is substantially longitudinally coextensive therewith. This tank comprises a transversely curved longitudinal shell 26 forming a substantially semi-cylindrical bottom wall 26a and a pair of substantially parallel at upright side walls 26h. Y Substantially at upright walls' connected with the shell 26 at the ends thereof form the end walls or beads27 and 230i' the tank. The tank 10 is closed at the top thereof' by a substantially flat longitudinal cover 29. y

The tank 10 is supported by the basel 11 and is connected therewith' in the above-mentioned spaced relation by a pair of longitudinally spaced upright supports 30 and 31'. The supports 3i) and 311 may be in the form of brackets or saddles fabricated fromv plate members or other structural components. ln this instance each of the'supports 3U and 31 comprisesY a pair of longitudinal upright front and rear ilanged plate members 32a and 3217 connected by a transverse upright plate member 32C, and a transversely curved platel member 33 forming a concave saddle top. These'plate members are welded or otherwise suitably connected together.

The lower edges of the rear plate members 321)y are suitably secured to the rear longitudinal frame member 26 of the base 11 and the lower edge of the front plate members 32a are secured to an intermediate longitudinal frame member a. The portion of the base 11 which projects forwardly from the supports and 31 formsa longitudinal shelf embodying the above-mentioned foundations 22 and 23 for the pump assemblies. The concave saddle tops formed bythe plate members 33 receive and support the tank 1u which is secured to such saddle tops by suitable welding.

As shown in the drawings, the tank 10v is provided with a transverse internal wall or bulkhead 34 forming a partition between the receiving chamber l2 and the treating chamber 13. The tank is also provided with a transverse internal' wall 35 forming a partition in the receiving chamber 12 and which divides the latter into a solids collecting compartment i211 and a liquid collecting compartment 12b. The partition 34 extends upwardly to the cover 29 such that the treating chamber 13 will be completely separated from the receiving chamber 12; The partition- 35, on the other hand, has its upper edge 35a spaced a short distance below the cover 2.9 such that this partition forms a bafe or dam over which liquid can flow from` the solids collectingl compartment 12a into the liquidV collecting compartment 12b.

The' tank 10 is also provided with a sewage'inlet connectionintheform of a conduit 36 extending through the cover 29 into the-solids collecting compartment 12a of the' receiving chamber 12'. A substantially L-shaped bafe 37 islocated in the/compartment 12a adjacent the lower end of the sewage inlet conduit 36 and serves the purpose of deliecting the incoming stream of sewage in aV lateral direction to preventv such' stream from flowing directly downwardly in the compartmentA 12a and agitating the solids which have already settled or collected in the bottom of this compartment@ As' sewage'V in the form of a mixture of liquid and solidy materials is delivered into the compartment 12a through the conduit 36, such sewage will till this compartment whereupon the clear liquid' will ilow over the edge 35a of the partition 35 into the liquid collecting compartment 12b. The solid material delivered into the compartment 12a`will settle to' the bottom of this compartment and will be retainedjherein as a sludge until such timeV as the' collected sludge is'to be discharged therefrom' in the manner hereinafter explained;

, The depth of sludge accumulation in the collecting 4 compartment 12a can be measured from time to time by means of a novel sounding device 38 with which the unit 19 is equipped. As shown in Figs. l and 5, the sounding device 33 comprises an upright stern 39 extending through a sleeve 4t) which is welded or otherwise suitably secured to the cover 29 and a transverse eeler plate 41 carried by the stem 39 and suitably secured to the lower end thereof. The sounding device 3S also includes a suitable handle 42 secured to the upper end of the stem 39 by which the device is adapted' tovr be manually grasped and operated. l A

In taking a sounding of the sludge accumulation' in the compartment 12a, the stem 39 is moved up and down through the sleeve 40 causing the feeler plate 41 to engage the surface of the sludge accumulation which will enable the operator to determine the location of such surface by noting the greater resistance to movement of the feeler plate into the body of sludge andthe lessened resistance to movement of the feeler plate through the body of liquid standing in the compartment 12a above the body of sludge. The feeler plate 41 can be: retained in a parked position or can be left in a'iXed' location designating the surface level of the accumulated sludge at any given time, by means of a collar d3 surrounding the stem 39 and adapted to be secured thereto by means of a clamping screw 44. When the collar 43 is thus secured to the stem 39 it forms a shoulder thereon which is engageable with the upper end of the sleeve 491er supporting the rod on the latter.

Y The tank 1t) is constructed of such a size that the collecting compartment 12a thereof will provide a storage space of suicient capacity to store the solid sewage materials being supplied during a predetermined time interval. Thus when the sewage treating apparatus is installed aboard a Steamship, the collecting compartment 12a would be of such capacity as to store the solid sewage'material of the ship for a predetermined time interval corresponding with the time interval which the ship usually remains in port. By thus collecting the solid portion of the ship sewage in the compartment 12a and' retaining the same therein as sludge while the ship remains in port, it will ordinarily not be necessary to discharge untreated sewage solids into the harbor waters during such period.

The liquid portion of the sewage which is supplied t'o the chamber 12 is also initially collected in the compartment 12a as indicated above, but when this compartment has become full, the liquid ows over the edge 35a of the partition 35 into the compartment 12b and is temporarily collected in the latter. When the liquid collected inthe compartment 12b reaches a predeterminedlevel it is transferred to the treating chamber 13 by operation ofthe transfer pump 14 and is treated witha disinfecting chemical which is supplied thereto in a manner to be presently explained.

The treated liquid sewage material or efiiuent is retained in the treating chamber 13 until it reaches apredetermined level whereupon the eftluent is discharged from this chamber by operation of the delivery pump 1S as will be presently explained. When the ship has left port, the sludge which has accumulated in the compartment 12a is discharged therefrom by operation'` of one or the other of the pumps 14 or 15in such a manner as todischarge the sludge overboard intounrestricted waters as Will be further explained' presently.

The sewage treating and disposal unit 19 includes a main conduit loop 45 located adjacent the tank 10 and here shown as comprising an upper conduitportion 45av having the discharge end i6 thereof communicating with the treating chamber 13 through the cover 29. The main conduit loop 4S also includes upright and' intermediate conduitportions 45h and 45o anda discharge end 41 controlled byv a' valve A- and adapted for connection' with conduit means extending to a point' of efiiuent disposal, such as the conduit portion 48 shown in Fig. 6 which leads to the outer shell 49 of the ship for discharging the eiuent overboard through an opening in such shell and through an outwardly opening check valve 50.

As shown in Figs. l and 6,'the transfer pump 14 has an intake 51 which is connected with the bottom of the liquid collecting compartment 12b by conduit means 52 having the valves B and C located therein in series relation. The discharge 55 of the transfer pump 14 is connected with the intermediate portion 45C of the main conduit loop 45 by conduit means 56. The point of connection of the discharge 55 of the transfer pump 14 with the main conduit loop 45 is located between a pair of valves D and E which are installed in the main conduit loop and to which further reference will be made hereinafter.

The discharge or overboard pump has its intake 59 connected with the bottom of the treating chamber 13 by a conduit means 60 having a pair of valves F and G therein in series relation. The discharge 63 of the delivery pump 15 is connected with the intermediate portion 45e of the main conduit loop 45 by conduit means 64. The connection of the discharge 63 of the delivery pump 15 with the conduit loop 45 is at a point located between the valves A and D of this conduit loop.

As shown in Fig. 6 a conduit 65 forms an intercommunicating connection between the intakes 55 and 63 of the transfer and delivery pumps 14 and 15. The conduit 65 has one end thereof connected with the intake conduit means 52 of the transfer pump at a point between series valves B and C. The other end of the conduit 65 is connected with the intake conduit means 60 of the delivery pump 15 at a point between the series valves F and G. The conduit 65 is controlled by a valve H.

For the removal of sludge from the solids collecting compartment 12a, a conduit 66 has one end thereof connected with the bottom of this compartment through a valve K and has its other end connected with the intake means 52 of the transfer pump 14 at a point between the series valves B and C. As shown in Fig. 6, the connection 65 permits the delivery pump 15 to be used for dischargingr sludge from the compartment 12a instead of the transfer pump 14 if that should be desirable.

For controlling the operation of the transfer and delivery pumps 14 and 15, the unit 19 is provided with suitable electric control apparatus Which includes contact members or probes extending into the liquid collecting compartment 12b and the treating chamber 13. In this instance there are three such probes, 68, 69 and 70 extending into the compartment 12b in depending relation from an insulating tting 71 carried by the cover 29. Three such probes 72, 73 ad 74 extend into the treating chamber 13 in depending relation from an insulating fitting 75 also carried by the cover 29.

The electric control apparatus of which the abovementioned probes form a part can be any conventional electric control apparatus of the switch relay type which Will operate to automatically start and stop the pumps 14 and 15 in sequence in response to predetermined changes of the liquid levels in the compartment 12b and the chamber 13. One suitable form of such electric control apparatus is illustrated in the wiring diagram of Fig. 8 to which further reference will be made hereinafter.

The probe 68 extends into the compartment 12b for only a relatively short distance and forms a portion of a high level alarm circuit. The probes 69 and 70 extend into the compartment 12b for a somewhat greater distance than the probe 68 and have their lower ends at the upper operating level for the liquid which collects in this cornpartment. The probe 69 constitutes a portion of the electric control circuit which causes automatic starting of the discharge pump 15 when the liquid in the compartment 12b reaches such upper operating level. The probe 70 constitutes a common electrode for the control circuits which are dependent on the liquid level in the compartment 12b.

72 of the treating chamber 13 extends into v for a distance such that the lower end of this probe is located at the upper operating level of the liquid which collects in this chamber. The probe 72 constitutes a portion of an electric control circuit which causes automatic stopping of the transfer pump 14 when the liquid in the treating chamber reaches such upper operating level. The probes 73 and 74 extend into the treating chamber 13 for a distance such that the lower ends of these probes are located adjacent the bottom of this chamber. The probe 73 forms a portion of a control circuit which causes automatic stopping of the delivery pump 15 when the level of liquid in this chamber falls to a level just below the lower end of this probe. The probe 74 constitutes a common electrode for the control circuits serving the treating chamber 13.

In the operation of the improved unit 19 as thus far described, it will be seen that when this unit is placed in operation at the desired point of use, the sewage inlet pipe 36 will be connected with the sewage system or sewer such that the sewage delivered to the tank 10 will gradually cause an accumulation of solids in the compartment 12a and an accumulation of clear liquid in the compartment 12b as explained above. In initially placing the unit 19 in operation, the treating chamber 13 is filled with water to the point where the upper operating level contacts the probe 72 to thereby energize the electric control apparatus to a condition corresponding with the stopped condition of the transfer pump 14, When the level of liquid in the collecting compartment 12b reaches its upper operating level and contacts the probes 69 and 70, the electric control apparatus will then be energized to cause the delivery pump 15 to be automatically started.

The operation of the delivery pump 15 causes the liquid or effluent of the treating chamber 13 to be withdrawn therefrom and discharged overboard through the conduit portion 47 and the conduit means 48. When the delivery pump 15 has operated for a period of time sufficient to cause the level of the effluent in the chamber 13 to be lowered to a point just below the lower ends of the probes 73 and 74, the electric control apparatus will cause the delivery pump 15 to be automatically stopped and will cause the transfer pump 14 to be automatically started. The operation of the transfer pump 14 caues the liquid collected in the compartment 12b to be withdrawn therefrom and to be delivered into the treating chamber 13 through the main conduit loop 45 The probe this chamber When the liquid thus delivered into the treating chamber 13 ills this chamber to the point where the upper level of the liquid contacts the probe 72, the electric control apparatus will be Ienergized to cause the transfer pump 14 to be automatically stopped. The liquid thus `delivered into the treating chamber 13 Will be retained therein until the liquid being collected in the compartment 12b again rises to the level where it will contact the probes 69 and 70 to again cause the delivery pump 15 to be automatically started. The period of time during which liquid is collecting in the compartment 12b provides a desired time interval or detention period during which the liquid of the chamber 13 is retained in the latter to be acted upon by the treating chemical.

If the unit 19 is not in proper operating condition such that the `delivery pump 15 will be automatically started when the liquid level in the compartment 12b contacts the probes 69 and 7l), the level will continue to rise and will ultimately contact the high level alarm probe 68. When this occurs a signal circuit of the electric control apparatus is energized to cause sounding of an alarm bell 1134 to give warning of such coded condition of the receiving chamber 12 of the tank 10.

During the normal 4operation of the unit 19, the sewage handled thereby is chemically treated with a desired or predetermined amount of a disinfecting chemical,

prefeibly' a chehi'icalv of the' chlorinating type'` such' as jhypochlrite', such thatthesewage deliveredfr'on the uni/twill; not be raw'I or untreated sew-'age such* as migttpllute thef surrounding waters. For this` purpose the uniti ,19` embodies treating chemical` supply means' which includes the above-mentionedpump 18 and which he' conveniently referred to as the chemical pump; The chemical supply'vmeans also includes a reservoir' 77' containing'a suitableV supply ofthe sodium hypoclilorite orV other treating chemical. Fig; l of the' drawings' shows the'v reservoir means for thechenrical supply as 'tripri'sing' a' plurality of `bottles` 77u.

The'chemicalp-ump- 1'8is' provided with a suctionlconduit iri the form of a tube`78 extending tothe res'ervior means and is also provided with 4a delivery conduit 79 whichppreferably h'a's branch portions 79h and 79h. The b`rar`1ch` conduit 7921 may be controllediby avalve Si! and is" here shown as having its deliveryv end communicating with the delivery portion 45a of the main conduit lop 45. l The branch portion' 79b`may be controlled by avalve 81 and is here sho-Wn as having it's delivery end communicating with' the sewage receiving chamber 12 at a' point adjacent the inlet conduit 36; preferablyy at a location between the end Wall 27 andthe baille 37 as shown in' Fig. 6. Y

The chemical pump 18 can be a pump of any construction suitable for this purpose, such as an adjustable stroke positive displacement' pump, and is driven by an electric niotoi' embodied therein or connected therewith. This is embodied in the unit 19' by being mounted' on a suitable bracket' or shelf 82 which is here shownas being secured to the upright front Wall 2Gb of the tank 10. The bottles 77a containing the supply of chemical are here shown as being supported by a shelf structure 83 which is also embodied in the unit 19 by being suitably secured'to theupright front wail 26?)- of the tank 1%;

When the treating chemical delivered by the pump' 13 i's supplied to` the conduit portion 45a' ofV the main conduit loop 45 as shown in the dnawings, thesewage being transferred fromv the compartment 12b` to the treating chamber 13 bythe transfer pump 14 will be effectively treated by an efficientmixing of a proportional amount of the chemical' withv the stream of sewage which is entering the compartment 13 through the conduit' connection46. The chemical pump 1S is normally operated under control of the electric control means such that this pump will .automatically operate 4intermittently and substantially simultaneously with the operation of the transfer pump i4. T huswhen the transfer pump 14 started automatically cal pump 18 will be automatically started substantially simultaneously and will discharge chemical through the conduit: branch 79d into the main conduit portion 45a fdr an etilcient mixing of this chemical with the sewage being' supplied to the treating chamber i3y by the transfe'r pump.

When the liquid has been transferred from the cornpartment 12b to the treating chamber i3 and the desired or predetermined amount of treating chemical has been mixed therewith asv justv explained above, the mixtureof sewage andwche-mical remains-in the treating chamber for a" period of timeV corresponding with that required to reiill the compartment 12b with liquid up to theVJ lvel ofv contact with the probes 69 and 76. The capacity of the compartmentv 12b is such that this detenti'on period will be of at least a predetermined minimum duration during which the mixture of sewage and chemical will be retained in the treating chamber 13 to permit-1 thechemical to accomplish its disinfecting action onV the sewage.

DuringA thel time that a ship equipped with the unit 19 normally remains in-port,theunit is operated automaticallyy -inthemanner already explained above. in which the liquidportion of theA sewage isintermittently transferred from the compartment 12b to the treating chamber `13 by the control means, the ohemif and treating chemical addedto' the sewage dur'ng' such transfer,I after'which the eiue'nt is discharged overboard from' the" treating chamber. The solids collectedi in the'j cmpartment 12a 'are retained therein and discharged overboard after the ship leaves' port, andl at a'- location where' the discharge of untreated sewage Willi not ber objectionable. Such discharge of the solids of sludge from the compartment 12a is accornplishedl by manual' controlA of one of thev pumps 14!I or 1'5; depending uponwhich ofthese pumps has been selected to' perform this work.Y j

If, however, the period ofV time which the ship is ex# pec'tedto remain-lin port is too long for the solids storageV capacity of the compartmentr 12a, the unit 1'9 canbe operated by supplying the treating chemical to the storagecompartment; 12a through thev branch conduit 79h" by a manually controlled continuous operation of the chemical pump 18. At' this time' the valve 80 of' the branch-conduitFl 79a is closed; When'theI unit 19 is being operated under tliese conditions, all of the sewage solids collected inl thel compartment 12a' will be treated with chemical while they remain in the compartment. Under thiscondition4 of: operation, liquid'will be transferred from the collecting compartment 12b to the treating chamber 13 intermittently by the pump 14 and the eiiluent will be intermittently discharged overboard from the treating chamberby the pump 154 and'these functions will be carrie'd" out automatically in the manner already explained ab'tnfe. When it becomes necessary to dischargel the sludge-trom the compartment 12a, it can then be done even'though theship'is still in port inasmuch as the sludge will' then-be a chemically treated sludge.

When thefship isfoperating out of port' and in unrestricti ed waters;thechemicalpump 18 ca'n betstopped: s'othat no treating'che'mical will then-be supplied to the sewage andthesewage will'be discharged overboard as untreated sewage by operation of the unit 19 in a manner which is otherwiseidenticalwith the automatic operation already explained above; The solid material which collects in the compartment 12a during this condition of operation willl need to be discharged from time to time andthis can be readily done by manual manipulation of the valves of the conduit means, and by manual control of the pump whichis used as thek sludge discharge pump and' which oan'be either the pump`14 or the pump 15 depending upon the setting -of the control valves.

Dring'lthe operation'of the ship in unrestricted Waters, it may be desirable to treat the sewage which is'being handled by the unit'19` in the same manner as the sewage which ishandledby thisunit when the ship is in port and, iny that case, the sewage which is discharged from the t'r'eating'chamber 13 will alwaysbe a treated sewageand the Settled solids or sludge which is discharged from the compartment 12a will be a chemically treated sludge whenever' the'operation ofk the unit is such that treating chemical is suppliedthrough the branch conduit 79h.

Reverting' to the description of the tank structure 10, it-shouldbe'explained that'thecompartments 12a and 12b and the treating chamber 13 are provided with bottom surfaces 84'which slope toward the outlet connections of these compartments. This sloping bottom surface can be obtained by providing a partial lling of varying thickness of cement 8S. The portion of the tank definingy the compartment 12a'is also provided with a pair of internal discharge nozzles 86 to which a supply of flushing water under pressurev can be connected for washing out this compartmentY after the sludge has been discharged therefrom. As shownl in the drawings, the nozzles 86 are-located-in' staggered relation in the compartment 12a, that is onlopposite sidesr of this compartment and facing each other, so that substantially all of the interior of this compartment will be; subjected to the streamsv ofi iiushing water. y

The tanlclt) ispneferably also providedfat'the top thereof with suitable'vent connectionsi87 and 88iwhich comthe upper portion of the receiving chamber 12 and the treating chamber 13 and with which suitable vent pipes can be connected. The cover 29 is preferably also provided with access openings or manholes for cleaning and inspection purposes and which openings are normally closed by suitable manhole covers 89, 90 and 91.

As has already been indicated above, the conduit means and the control valves of the unit 19 are such that the pump 14 will be used as a transfer pump under normal automatic control but under manual control can also be used as a delivery pump, and likewise, the pump 15 will be used as a delivery or overboard pump under normal automatic control but under manual control can also be used as a transfer pump. The conduit means and the control valves of the unit 19 are also such that the discharge of sludge from the compartment 12a can be accomplished by use of either the pump 14 or the pump 15 under manual control for this purpose. The use of the pumps 14 and 15 for these different functions depends upon the setting of the control valves and, as a simple explanation of the differ ent settings for these valves, reference is made to the valve setting diagram of Fig. 7. This diagram shows graphically the functions of the pumps 14 and 15 during the different operating conditions of the unit 19 and the corresponding settings of the various control valves which will result in the attainment of the desired functions by these pumps.

As has been indicated above, `the electric control apparatus for automatically controlling the operation of the transfer and delivery pumps 14 and 15 and the operation of the chemical pump 18 can be electric control apparatus of a conventional type and for that reason a detailed description of the electrical apparatus is considered unnecessary. In connection with this electrical control apparatus it is deemed suicient to explain that, as shown in the wiring diagram of Fig. 8, it comprises a transformer 92 and a group of liquid level responsive pump control relay switches 93, 94 and 95 and a group of liquid level responsive signal control relay switches 96 and 97. This control apparatus also comprises pump starting switch units 9S and 99. All of the devices just mentioned are suitably located in a control box 100 which is mounted on the end wall 27 of the tank 10 and is normally closed by a cover 101.

By locating the electrical control apparatus in the boX 100 it can be connected in operative relation with the electric motors of the pumps and with the control probes of the tank 10 such that the unit 19 can be fully tested in the shop or factory in which it is built and prior to the delivery or shipment of the unit for nal installation. The location of the electric control apparatus in the box 100 also protects this apparatus from harmful blows or from damaging contact by moisture or other harmful agents.

This electric control apparatus also includes signal lamps 102 and 103, a signal bell 104, and manually operable switches 105, 106 and 107. The signal bell 104 and the manual switches 105, 106 and 107 are preferably mounted on the inside of the cover 101 of the control box 100. The bell 104 and the lamps 102 and 103 are signal devices for automatically indicating an abnormal condition in the functioning of the unit 19, or of a plurality of such units as when similar units are located at different points on the same ship. The signal lamps 102 and 103 can be located on the outside of the box 100 or at any other desired place or places on the ship.

In connection with this electric control apparatus it can be further briefly explained that the relay switch 93 is a pump circuit holding switch which is responsive to a rising liquid level and the relay switch 94 is a pump circuit holding switch which is responsive to a falling liquid level. The relay switches 96 and 97 are high liquid level responsive switches which control the lamps 102 and 103 and the signal bell 104. The switch 105 is a push button municate respectively with 10 switch which stops the ringing of the bell 104. The switcli device 98 is an automatic starting switch for the delivery pump 1S and the switch device 99 is an automatic starting switch for the transfer pump 14 and the chemical pump 18.

The switches 106 and 107 are selector switches for the transfer and delivery pump, respectively, for shifting from automatic operation to manual operation or vice versa. Each of the latter switches has an intermediate open position and contact settings 108 and 109 for automatic and manual control of the operation of the transfer and delivery pumps. When these switches are in their open position the pumps will be stopped and inoperative but when the movable switch members of these switches have been manually engaged with the contacts 108, the transfer and delivery pumps will be under the automotive control of the relay switches and starting switches mentioned above. When one or the other of the movable switch members of these switches is manually engaged with the contacts 109, the corresponding transfer or delivery pump will be running and will then be operating under manual control.

From the foregoing detailed description and the accompanying drawings, it will now be readily understood that this invention provides a novel form of automatic sewage treatment and disposal unit which can be prefabricated and assembled in a shop or factory and can be tested out as such a complete unit prior to delivery thereof to the point of linal installation. It will also be understood that the sewage treatment and disposal unit provided by this invention will permit the liquid portion of the sewage of a ship to be chemically treated while the ship is in port and the solid portion of the sewage to be stored for discharge overboard into unrestricted waters after the ship leaves port. It will also be seen that the unit 19 is of such construction that it is very flexible and adaptable in its operation such that it can be operated in various different ways for handling the ships sewage to best advantage and in accordance with regulations covering the discharge of sewage from ships into harbor waters.

Although the automatic sewage treatment and disposal unit of this invention has been illustrated and described herein to a detailed extent, it will be understood of course that the invention is not to be regarded as being limited correspondingly in scope but includes all changes and modifications coming within the terms of the claims hereof.

Having thus described our invention, we claim:

1. A prefabricated sewage disposal unit for shipboard use comprising; a unitary structure constituting a preformed base; a substantially closed tank mounted on said base and having therein a sewage receiving and storage chamber and a sewage treating chamber; a transfer pump;

aV delivery pump; driving motors connected with said pumps to drive the same; means on said base forming foundations for said transfer and delivery pumps and their driving motors and having said pumps and motors mounted thereon; conduit means connecting the intake of said transfer pump with said receiving chamber; conduit means connecting the discharge of said transfer pump with said treating chamber; conduit means connecting the intake of said delivery pump with said treating chamber; and conduit means extending from said delivery pump and adapted for connection with an overboard discharge means; said base, tank, pumps, driving motors and conduit means being all assembled in their connected and operative relation to constitute a prefabricated unit adapted to be tested and transported as such prior to installation for its intended regular service operation on aship.

2. A prefabricated sewage disposal unit particularly for ships comprising; a unitary structure constituting a preformed base; a substantially closed tank mounted on said base yand having therein a receiving and storage chamber and a treating chamber; a transfer pump; an overboard pump; driving motors connected with said l76 pumps to drive the same; means on said base forming armste foundations for saidv` transfer and overboard pumps and their driving-motors and having said pumps and'motors mounted thereon; conduit means forming. a loop ,having one endthereofconnected with` said treatingI chamber and having its other end adapted for connection with an overboard discharge means; conduit means connecting the intakes of said transfer andi overboard pumps with said receiving and treating chambers;- conduit means connecting the discharges of said pumps with the-,intermediatel portion of said loop; and valves controlling all Iof said conduit means;l said base, tank, pumps, driving motors, conduit means and valves being` all assembled in their connected and operative relation to constitute a prefabricatedunit adapted to be tested and transported as such prior to` installationfor its intcndedregular service operation on'a ship.

3; A-prefabricated sewage treatment and disposal unit for shipboard' use comprising; a unitary structure constitutihg apreformed base; a substantially closed tank mounted on said base and having therein a sewage-receiving and storage chamber and a sewage treating chamber; a transfer pump; a. delivery pump; driving motors connected with said pumps to drive the same; means on said base formingV foundations for said transfer and delivery pumpsand their driving motors and having saidspumps and motors mounted thereon; conduit means operably connecting` said' transfer and deilvery pumps with said receiving'land treating chambers and providing for the transfe'r of sewage from said; receiving chamber to said treating chamber and the delivery of treated sewage from said treatingfchamber; treating chemical supply means operable tosupply treating chemical for mixing with the sewage delivered to said treating chamber; and electric control means responsive to predetermined liquid levels in said receiving and treating chambers and elective on said driving motors for automatically causing intermittent operation of said pumpsy in sequence; said base, tank, pumps, driving motors, chemical supply means, and electric control meansbeing all assembled in their connected and operative relation to constitute a substantially complete pr'efabricated unit adapted to be prelirninarily tested and transported as suchprior to installation for its intended regular service operation on a ship. l, s s o 4. A prefabricated sewage treatment and disposal unit as deiined inclaim 3 in which said treatingchemical supply means includes a motor driven chemical pumpgfand lin which said electric control means includes means for causing operation of the chemical pump substantially simultaneously with the operation of said transfer pump.

5.y A prefabricated sewage treatment and disposal unit as deiined in claim 3 in-which said electric-control means includes'contact probes extending into said receiving and treating-chambers and switch means electricallyl connected with said probes and effective to control said-niotors;and in which a control box mounted on saidunit has said switch means housedtherein. Y

6; A sewage treatment and' disposal unit' comprising, substantially closed tank structure having therein a sewage receiving and storage chamber and a sewage treating chamber, a transfer pump: having its intake connected with said receiving chamber' and its dischargeconnectedwith said'treatingchamber, a delivery pump havingy its intake connected with said treating'chamber and its discharge connected-Wuhan effluent disposal point,;drivng motors connected withsaid pumps" for driving the'same, means operable tosupply treatingchemical for mixing with the sewage delivered to said treatingchamber by said transfer pump, and electric control means responsive to predetermined liquidlevels in said receiving' and V4treating chambers and effective on said driving motors" for automatically causing intermittent operationl'of-V said pumps including-means responsive to the rise of liquid tpj a^predetermined upper level in said storage chamber 4for starting said -deliverypump and means responsive v*to 'the change in' the liquid level in said treating chamber'from a predetermined upper level to a predetermined lower level and vice versa for starting and stopping said transfer pump.

7'. A sewage treatment and disposal unit comprising, substantially closedv tank structure having therein a sewage receiving and storage chamber and a sewage treating chamber, a transfer pump having its intake connected with said receiving chamber and its discharge connectedA with said treating chamber, a delivery pump having its intake connected-*with said treating chamber and its discharge connectedwith an efuent disposalV point, driving motors connected with said pumps for driving the same, means operable to supply treating chemical for mixing with the sewage delivered to said treating chamber by said transfer pump, and electric control means responsive to predetermined liquid levels in said receiving and treating chambers` and etfective on said driving motors for automatically causingv intermittent operation of said pumps including means responsive to the rise of liquid to a predetermined upper level in said storage chamber to cause the starting of said delivery pump and means responsive to the change in the liquid level in said treating chamber from a predetermined upper level to a predetermined lower level and vice versa to cause the starting and stopping of said transfer pump, the capacity of said sewagev receiving chamber being such that the iilling of said' receiving chamber to a level for causing the starting of said delivery by said electric control means provides a predetermined time interval during which the sewage of said treating chamber is retained therein in contact with said treating chemical.

8. A sewage treatment and disposal unit as dened in claim 6 in which the treating chemical supply means has its discharge connected with the discharge of said transfer pump for mixing contact of said chemical with the stream of sewage being delivered by said transfer pump at a point in advance of the admission of said stream to said treating chamber.

9. Asewage treatment and disposal unit as detined in claim 6 in which the treating chemical supply means is a motor driven chemical pump having its discharge connected with the discharge of said transfer pump for mixing contact of said chemical with the stream of sewage being delivered by said transfer pump at a point in advance of the admission of said stream to said treating chamber, and in which said electric control means also includes means eitective on the driving motor of said chemical pump for automatically causing starting and stopping of the chemical pump substantially simultaneously with the starting and stopping of said transfer pump.'

10. A sewage treatment and disposal unit comprising, substantially closed tank structure having therein a sewage receiving chamber and a sewage treating chamber, means dividing said receiving chamber into a solids storage compartment and a liquid storage compartment, a transfer pump having its intake connected with said liquid storage compartment and its discharge connected with said treating chamber, a delivery pump having its intake connected with said treating chamber and its discharge connected with an effluent disposal point, electric motors connected with said pumps for driving the same, means operable tov supply treating chemical for mixing with the sewage delivered to said treating chamber by said transfer pump', and' electric control means responsive to predetermined liquid levels in said liquid storage compartment and in said treating chamber and effective on said electric motors for automatically causing intermittent operation ofsaid pumps in sequence such that the operation of said delivery pump takes place while said transfer pump is stopped and the operation of said transfer pump takes place while said delivery pump is stopped.

l1. A sewage treatment and disposal uni-t comprising, substantiallyclosed tank structure having therein a sewage receiving chamber and a sewage treating chamber, means dividing said receiving chamber into a solids storage compartment and a liquid storage compartment, a transfer pump having its intake connected with said liquid storage compartment and its discharge connected with said treating chamber, a delivery pump having its intake connected with said treating chamber and its discharge connected with an effluent disposal point, electric motors connected with said pumps for driving the same, means operable to supply treating chemical for mixing with the sewage delivered to said treating chamber by said transfer pump, and electric control means responsive Ito predetermined liquid levels in said liquid storage compartment and in said treating chamber and effective on said electric motors for automatically causing intermittent operation of said pumps in sequence, Athe capacity of said liquid storage compartment being such that the lling of said liquid storage compartment to a level for causing energization of said electric control means provides a predetermined time interval during which the sewage of said treating chamber is retained therein in contact with said treating chemical.

12. A prefabricated sewage treatment and disposal unit particularly for ships comprising; an elongated unitary structure constituting a preformed substantially rigid horizontal base; an elongated substantially closed tank spaced above said base and having therein a receiving chamber and a treating chamber; means in said tank dividing said receiving chamber into a solids collecting compartment and a liquid collecting compartment; upright supports extending between said base and tank and mounting the latter on said base in such spaced relation thereto; a transfer pump; an overboard pump; electric motors connected with said pumps to drive the same; means on said base forming foundations for said transfer and overboard pumps and their driving motors and having said pumps and motors mounted thereon; conduit means forming a conduit loop having one end thereof connected with said treating chamber and having its other end adapted for connection with an overboard discharge means; conduit means connecting the intake of said overboard pump with said treating chamber; conduit means connecting the discharge of said overboard pump with an intermediate portion of said conduit loop; conduit means connecting the intake of said transfer pump with said solids and liquid storage compartments; conduit means connecting the discharge of said transfer pump with said intermediate pottion of said conduit loop; an interconnecting conduit means connecting the intakes of said transfer and overboard pumps; valves controlling all of said conduit means; treating chemical supply means including a motor driven chemical pump having discharge means connected with said conduit loop and with said solids storage compartment; a control box; and electric control means including contact probes extending into said liquid storage compartment and into said treating chamber and switch means located in said control box; said electric control means being responsive to predetermined liquid level changes in said liquids storage chamber and in said treating chamber and being effective on said motor driven chemical pump and on said transfer and overboard pumps to automatically cause a timed intermittent operation of said chemical pump and an intermittent operation of said overboard and transfer pumps in sequence; said base, tank, supports, transfer pump, overboard pump, chemical pump, driving motors, conduit means, valves, control box and electrical control means being all assembled in connected relation to constitute a factory-built unit adapted to be tested and transported as such for installation in a ship.

References Cited in the le of this patent UNITED STATES PATENTS 292,046 Powers Jan. 15, 1884 1,223,427 Scarborough Apr. 24, 1917 1,255,170 Jacobus Feb. 5, 1918 1,291,628 Parsons Jan. 14, 1919 1,956,463 Lyon Apr. 24, 1934 2,082,847 Petty June 8, 1937 2,131,711 Porteous Sept. 27, 1938 2,245,767 Eickmeyer et al. June 17, 1941 2,356,786 Harman et al Aug. 29, 1944 2,557,438 Johnson June 19, 1951 2,640,807 Rice June 2, 1952 2,709,680 Watson May 31, 1955 

1. A PREFABRICATED SEWAGE DISPOSAL UNIT FOR SHIPBOARD USE COMPRISING; A UNITARY STRUCTURE CONSTITUTING A PREFORMED BASE; SUBSTANTIALLY CLOSED TANK MOUNTED ON SAID BASE AND HAVING THEREIN A SEWAGE RECEIVING AND STORAGE CHAMBER AND A SEWAGE TREATING CHAMBER; A TRANSFER PUMP; A DELIVERY PUMP; DRIVING MOTORS CONNECTED WITH SAID PUMPS TO DRIVE THE SAME; MEANS ON SAID BASE FORMING FOUNDATIONS FOR SAID TRANSFER AND DELIVERY PUMPS AND THEIR DRIVING MOTORS AND HAVING SAID PUMPS AND MOTORS MOUNTED ATHEREON; CONDUIT MEANS CONNECTAING THE INTAKE OF SAID TRANSFER PUMP WITH SAID RECEIVING CHAMBER; CONDUIT MEAND CONNECTING THE DISCHARGE OF SAID TRANSFER PUMP WITH SAID TREATING CHAMBER; CONDUIT MEANS CONNECTING THE INTAKE OF SAID DELIVERY PUMP WITH SAID TREATING CHAMBER; AND CONDUIT MEANS EXTENDING FROM SAID DELIVERY PUMP AND ADAPTED FOR CONNECTION WITH AN OVERBOARD DISCHARGE MEANS; SAID BASE, TANK, PUMP, DRIVING MOTORS AND CONDUIT MEANS BEING ALL ASSEMBLED IN THEIR CONNECTED AND OPERATIVE RELATION TO CONSTITUTE A PREFABRICATED UNIT ADAPTED TO BE TESTED AND TRANSPORTED AS SUCH PRIOR TO INSTALLATION FOAR ITS INTENDED REGULAR SERVICE OPERATION ON A SHIP. 